In the electrophotographic process, various charging devices are needed to charge a photoreceptor (“receptor”), recharge a toner layer, charge an intermediate transfer belt for electrostatic transfer of toner, or charge a sheet of media, such as a sheet of paper. Conventional non-contact charging devices typically apply high DC voltages to wires or pins, such as corotrons, scorotrons, and dicorotrons, to produce ions for charging. Problems arise because the undesired highly reactive oxidizing species that are also generated in the process degrade the photoreceptor and causes air pollution. Alternative contact charging devices use high AC voltages to charge small diameter drums. Problems arise because the undesired highly reactive oxidizing species that are also generated in the process degrade the photoreceptor and may cause air pollution. Alternative contact charging devices use high AC voltages to charge small diameter drums. Problems arise with contact charging devices because the reactants generated along with mechanical wear serve to also degrade the photoreceptor. Moreover, conventional charging devices require high voltages and a large size (e.g., the length in the process direction) for high process speed electrophotographic machines.
Thus, there is a need to overcome these and other problems of the prior art to provide a method and system for direct charging of the receptor, and to reduce the undesired reactive oxidizing species generated through the charging process.